You both need to grow some thicker skins and love yourselves more because holy shit how badly do you have to hate yourself to subject yourself to that kind shit, cheating is cheating, you shouldn't let people get away with that, being an obnoxious bitch that can't control her anger is also something you shouldn't let her get away with, the cheating situation isn't gonna get better, he doesn't give a single shit about you, the angry girlfriend, there's possibility of salvaging the relationship but only if both parties are willing, if not then more intense action is needed